Ophthalmic ultrasonic diagnostic apparatus

Abstract

To provide an ophthalmic ultrasonic diagnostic apparatus capable of obtaining measurement result with high reliability without lengthy measurement. The apparatus which measures constituent parts of an eye through A-mode includes an ultrasonic probe for A-mode measurement including a transducer emitting an ultrasonic wave into the eye and receiving reflected echoes from tissues of the parts, calculation means for judging whether signals of the echoes are appropriate and calculating measurement values of the parts based on the signals, a memory storing the calculated values, grouping means for setting grouping ranges having predetermined ranges of permissible dispersion with reference to the measurement values and determining that either the grouping range previously set or the grouping range newly set based on the obtained measurement value remains, and central value calculating means counting the numbers of the measurement values falling within the grouping ranges and calculating a central value based on the measurement values.

1. An ophthalmic ultrasonic diagnostic apparatus which measures constituent parts of an examinee's eye through A-mode, the apparatus comprising:
 an ultrasonic probe for A-mode measurement including a transducer which emits an ultrasonic wave into the examinee's eye, and receives echoes reflected respectively from tissues of the constituent parts; 
 calculation means for judging whether signals of the received reflected echoes are appropriate by analyzing the reflected echo signals and calculating measurement values of the constituent parts based on the reflected echo signals which are judged as appropriate; 
 a memory which stores the calculated measurement values; 
 grouping means for setting grouping ranges each having a predetermined permissible dispersion range with reference to the measurement value, and determining that either one of;
 the grouping range which is previously set; and 
 the grouping range which is newly set based on the obtained measurement value; and 
 
 central value calculating means for counting the number of the measurement values which fall within the respective grouping ranges, and calculating a central value based on the measurement values which fall within the grouping range such that the number of the measurement values falling within the grouping range reaches a predetermined number. 
 
   
   
     2. The ophthalmic ultrasonic diagnostic apparatus according to  claim 1 , wherein the grouping means sets the grouping ranges with reference to the measurement value which is obtained first. 
   
   
     3. The ophthalmic ultrasonic diagnostic apparatus according to  claim 1 , wherein the grouping means sets the grouping ranges in steps of a predetermined width in a range including the lowest and highest measurement values stored in the memory. 
   
   
     4. The ophthalmic ultrasonic diagnostic apparatus according to  claim 1 , wherein the grouping means sets the grouping ranges with reference to the measurement values at every obtainment of the measurement values. 
   
   
     5. An ophthalmic ultrasonic diagnostic apparatus which measures constituent parts of an examinee's eye through A-mode, the apparatus comprising:
 an ultrasonic probe for A-mode measurement including a transducer which emits an ultrasonic wave into the examinee's eye, and receives echoes reflected respectively from tissues of the constituent parts; 
 a calculation unit which judges whether signals of the received reflected echoes are appropriate by analyzing the reflected echo signals and calculates measurement values of the constituent parts based on the reflected echo signals which are judged as appropriate; 
 a memory which stores the calculated measurement values; 
 a grouping unit which sets grouping ranges each having a predetermined permissible dispersion range with reference to the measurement value, and determines that either one of;
 the grouping range which is previously set; and 
 the grouping range which is newly set based on the obtained measurement value; and 
 a central value calculating unit which counts the number of the measurement values which fall within the respective grouping ranges, and calculates a central value based on the measurement values which fall within the grouping range such that the number of the measurement values falling within the grouping range reaches a predetermined number. 
 
 
   
   
     6. The ophthalmic ultrasonic diagnostic apparatus according to  claim 5 , wherein the grouping unit sets the grouping ranges with reference to the measurement value which is obtained first. 
   
   
     7. The ophthalmic ultrasonic diagnostic apparatus according to  claim 5 , wherein the grouping unit sets the grouping ranges in steps of a predetermined width in a range including the lowest and the highest measurement values stored in the memory. 
   
   
     8. The ophthalmic ultrasonic diagnostic apparatus according to  claim 5 , wherein the grouping unit sets the grouping ranges with reference to the measurement values at every obtainment of the measurement values.